Plenty of pepper or red pepper flakesThe potatoes: "I halve my potatoes lengthwise, then slice them slightly thinner than 1/8 -inch. Fry them in 2 inches of olive oil and half sunflower oil, or less. I don't like to let them get too golden, and I let only about half of them get crunchy. I drain them on three layers of paper towels."The sauce: "The so-called Greek yogurt you get is not the best kind for this. Basically very few of these thick yogurts are made with the traditional culture. I use regular cow or preferably sheep or goat's milk yogurt -- the sourness compensates for the sweet-and-oily potatoes. Combine the yogurt, feta, mustard and quite a bit of ground pepper or Aleppo pepper flakes. I once added some lemon zest, which you may or may not like. Help yourself to a few potatoes, take some sauce on the side, and dip each bunch of forked potatoes in the sauce and eat them."